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Django select only rows with duplicate field values
...ango. The problem is that this will return a ValuesQuerySet with only name and count. However, you can then use this to construct a regular QuerySet by feeding it back into another query:
dupes = Literal.objects.values('name')
.annotate(Count('id'))
.or...
Dynamic variable names in Bash
...
Use an associative array, with command names as keys.
# Requires bash 4, though
declare -A magic_variable=()
function grep_search() {
magic_variable[$1]=$( ls | tail -1 )
echo ${magic_variable[$1]}
}
If you can't use associative arrays (e.g., you m...
How do I remove all .pyc files from a project?
I've renamed some files in a fairly large project and want to remove the .pyc files they've left behind. I tried the bash script:
...
How does Django's Meta class work?
...ciated database table name, whether the model is abstract or not, singular and plural versions of the name etc.
Short explanation is here: Django docs: Models: Meta options
List of available meta options is here: Django docs: Model Meta options
For latest version of Django: Django docs: Model Met...
Repeat string to certain length
...
def repeat_to_length(string_to_expand, length):
return (string_to_expand * ((length/len(string_to_expand))+1))[:length]
For python3:
def repeat_to_length(string_to_expand, length):
return (string_to_expand * (int(length/len(string_to_expand))+1))[:l...
Average of 3 long integers
...ides all three values (it floors the values, so you 'lose' the remainder), and then divides the remainder:
long n = x / 3
+ y / 3
+ z / 3
+ ( x % 3
+ y % 3
+ z % 3
) / 3
Note that the above sample does not always work properly when h...
Specify JDK for Maven to use
I am trying to build a Hudson plugin I've modified and it requires jdk1.6. This is fine, but I don't see how I can tell maven where the different jdk is. I've found few mentions on the internet but they don't seem to apply to me. Some suggest adding some config to .m2/settings.xml but I don't have...
How can I maintain fragment state when added to the back stack?
...return to FragmentA (by pressing back), a totally new FragmentA is created and the state it was in is lost. I get the feeling I'm after the same thing as this question, but I've included a complete code sample to help root out the issue:
...
How to JSON serialize sets?
I have a Python set that contains objects with __hash__ and __eq__ methods in order to make certain no duplicates are included in the collection.
...
When should I use nil and NULL in Objective-C?
... technically, they are exactly equal, you can send messages to both nil and to NULL. Idiomatically though nil is usually used to represent an object
– cobbal
Oct 14 '09 at 5:43
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